Two-Stage Non-Orthogonal Multiple Access over Power Line Communication Channels

Non-orthogonal multiple access (NOMA) has recently been proposed for dual-hop cooperative relaying power line communication (PLC) systems. Unlike conventional NOMA-PLC schemes which deploy NOMA only at the relay, this paper proposes to enhance the performance of such systems by implementing the principle of NOMA at both the source and relaying modems. The system performance is evaluated in terms of the average sum capacity for which analytical expressions are derived for both the improved and conventional NOMA-PLC systems. Throughout our analysis, the PLC channel is assumed narrow-band modeled with log-normal amplitude distribution and the total PLC noise consists of both background and impulsive noise. Monte Carlo simulations are provided to corroborate the accuracy of our theoretical analysis. The derived expressions are utilized to examine the impact of various system parameters on the average capacity performance; this includes: impulsive noise probability, network branching, power allocation coefficients and transmit power. The optimization problem of the power allocation coefficients is also addressed for both NOMA-PLC systems under consideration. Results reveal that significant gains in the average capacity can be attained with the improved NOMA-PLC approach compared to the conventional system. In addition, the improved system is able to meet a given performance requirement with smaller transmit power offering more relaxed electromagnetic compatibility issues associated with PLCs. Finally, it is demonstrated that optimizing the power allocation coefficients at both the source and relay modems is crucial to maximize performance

Multi-Layer Integration of Heterogeneous Wireless Sensor Networks for Smart Home Optimization

Wireless sensor-based smart home systems are increasingly gaining prevalence, offering new opportunities for automation and an improved quality of life. However, the seamless integration of multi-layer wireless sensor networks remains a significant challenge. This article delves into a comprehensive approach to integrate wireless networks that employ distinct protocols, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, and LoRa, within the context of Home Assistant-based smart homes. The article explores architectural solutions and data transformation methods, and presents the outcomes of performance experiments, as well as the stability of multi-layered wireless sensor networks. These findings culminate in the identification of an optimal configuration. The formulation of this research problem sets the stage for novel perspectives in the development of efficient and adaptive smart homes